Remove the quad_precision_float feature gate

The f128 type has very little support in the compiler and the feature is
basically unusable today. Supporting half-baked features in the compiler can be
detrimental to the long-term development of the compiler, and hence this feature
is being removed.

src/librustc/front/feature_gate.rs

@@ -64,7 +64,7 @@ static KNOWN_FEATURES: &'static [(&'static str, Status)] = &[
     ("overloaded_calls", Active),
     ("unboxed_closure_sugar", Active),
 
-    ("quad_precision_float", Active),
+    ("quad_precision_float", Removed),
 
     // A temporary feature gate used to enable parser extensions needed
     // to bootstrap fix for #5723.
@@ -91,7 +91,6 @@ enum Status {
 /// A set of features to be used by later passes.
 pub struct Features {
     pub default_type_params: Cell<bool>,
-    pub quad_precision_float: Cell<bool>,
     pub issue_5723_bootstrap: Cell<bool>,
     pub overloaded_calls: Cell<bool>,
 }
@@ -100,7 +99,6 @@ impl Features {
     pub fn new() -> Features {
         Features {
             default_type_params: Cell::new(false),
-            quad_precision_float: Cell::new(false),
             issue_5723_bootstrap: Cell::new(false),
             overloaded_calls: Cell::new(false),
         }
@@ -425,7 +423,6 @@ pub fn check_crate(sess: &Session, krate: &ast::Crate) {
     sess.abort_if_errors();
 
     sess.features.default_type_params.set(cx.has_feature("default_type_params"));
-    sess.features.quad_precision_float.set(cx.has_feature("quad_precision_float"));
     sess.features.issue_5723_bootstrap.set(cx.has_feature("issue_5723_bootstrap"));
     sess.features.overloaded_calls.set(cx.has_feature("overloaded_calls"));
 }

src/librustc/metadata/tydecode.rs

@@ -330,7 +330,6 @@ fn parse_ty(st: &mut PState, conv: conv_did) -> ty::t {
           'D' => return ty::mk_mach_int(ast::TyI64),
           'f' => return ty::mk_mach_float(ast::TyF32),
           'F' => return ty::mk_mach_float(ast::TyF64),
-          'Q' => return ty::mk_mach_float(ast::TyF128),
           _ => fail!("parse_ty: bad numeric type")
         }
       }

src/librustc/metadata/tyencode.rs

@@ -221,7 +221,6 @@ fn enc_sty(w: &mut MemWriter, cx: &ctxt, st: &ty::sty) {
             match t {
                 TyF32 => mywrite!(w, "Mf"),
                 TyF64 => mywrite!(w, "MF"),
-                TyF128 => mywrite!(w, "MQ")
             }
         }
         ty::ty_enum(def, ref substs) => {

src/librustc/middle/resolve.rs

@@ -770,7 +770,6 @@ impl PrimitiveTypeTable {
         table.intern("char",    TyChar);
         table.intern("f32",     TyFloat(TyF32));
         table.intern("f64",     TyFloat(TyF64));
-        table.intern("f128",    TyFloat(TyF128));
         table.intern("int",     TyInt(TyI));
         table.intern("i8",      TyInt(TyI8));
         table.intern("i16",     TyInt(TyI16));

src/librustc/middle/trans/debuginfo.rs

@@ -1621,7 +1621,6 @@ fn basic_type_metadata(cx: &CrateContext, t: ty::t) -> DIType {
         ty::ty_float(float_ty) => match float_ty {
             ast::TyF32 => ("f32".to_string(), DW_ATE_float),
             ast::TyF64 => ("f64".to_string(), DW_ATE_float),
-            ast::TyF128 => ("f128".to_string(), DW_ATE_float)
         },
         _ => cx.sess().bug("debuginfo::basic_type_metadata - t is invalid type")
     };

src/librustc/middle/trans/reflect.rs

@@ -148,7 +148,6 @@ impl<'a, 'b> Reflector<'a, 'b> {
           ty::ty_uint(ast::TyU64) => self.leaf("u64"),
           ty::ty_float(ast::TyF32) => self.leaf("f32"),
           ty::ty_float(ast::TyF64) => self.leaf("f64"),
-          ty::ty_float(ast::TyF128) => self.leaf("f128"),
 
           // Should rename to vec_*.
           ty::ty_vec(ref mt, Some(sz)) => {

src/librustc/middle/trans/type_.rs

@@ -88,10 +88,6 @@ impl Type {
         ty!(llvm::LLVMDoubleTypeInContext(ccx.llcx))
     }
 
-    pub fn f128(ccx: &CrateContext) -> Type {
-        ty!(llvm::LLVMFP128TypeInContext(ccx.llcx))
-    }
-
     pub fn bool(ccx: &CrateContext) -> Type {
         Type::i1(ccx)
     }
@@ -135,7 +131,6 @@ impl Type {
         match t {
             ast::TyF32 => Type::f32(ccx),
             ast::TyF64 => Type::f64(ccx),
-            ast::TyF128 => Type::f128(ccx)
         }
     }
 

src/librustc/middle/ty.rs

@@ -694,7 +694,6 @@ mod primitives {
     def_prim_ty!(TY_U64,    super::ty_uint(ast::TyU64),     12)
     def_prim_ty!(TY_F32,    super::ty_float(ast::TyF32),    14)
     def_prim_ty!(TY_F64,    super::ty_float(ast::TyF64),    15)
-    def_prim_ty!(TY_F128,   super::ty_float(ast::TyF128),   16)
 
     pub static TY_BOT: t_box_ = t_box_ {
         sty: super::ty_bot,
@@ -1272,9 +1271,6 @@ pub fn mk_f32() -> t { mk_prim_t(&primitives::TY_F32) }
 #[inline]
 pub fn mk_f64() -> t { mk_prim_t(&primitives::TY_F64) }
 
-#[inline]
-pub fn mk_f128() -> t { mk_prim_t(&primitives::TY_F128) }
-
 #[inline]
 pub fn mk_uint() -> t { mk_prim_t(&primitives::TY_UINT) }
 
@@ -1314,7 +1310,6 @@ pub fn mk_mach_float(tm: ast::FloatTy) -> t {
     match tm {
         ast::TyF32  => mk_f32(),
         ast::TyF64  => mk_f64(),
-        ast::TyF128 => mk_f128()
     }
 }
 

src/librustc/middle/typeck/astconv.rs

@@ -355,13 +355,6 @@ pub fn ast_ty_to_prim_ty(tcx: &ty::ctxt, ast_ty: &ast::Ty) -> Option<ty::t> {
                             Some(ty::mk_mach_uint(uit))
                         }
                         ast::TyFloat(ft) => {
-                            if ft == ast::TyF128 && !tcx.sess.features.quad_precision_float.get() {
-                                tcx.sess.span_err(path.span, "quadruple precision floats are \
-                                                              missing complete runtime support");
-                                tcx.sess.span_note(path.span, "add \
-                                                               #[feature(quad_precision_float)] \
-                                                               to the crate attributes to enable");
-                            }
                             check_path_args(tcx, path, NO_TPS | NO_REGIONS);
                             Some(ty::mk_mach_float(ft))
                         }